1.Take a pan and boil milk, boil till it reduces to 1 and 1/2 cups. Allow it to cool. To this boiled milk add pista, sugar, cardamom and grind this mixture.2.Combine the ice cream, milk to the pista or pistachio butter*, and food coloring (if using) in a blender and pulse on high-speed until the mixture is smooth.3.Pour into a tall, clear glass. and sprinkle the chopped roasted nuts to decorate. Refrigerate it and Serve chilled.

Notes

*Pistachio Butter

If you cannot find pistachio butter at the grocery store, you can make your own by combining 1 cup of pistachios, 1 tablespoon of light vegetable oil, and a pinch of sea salt in a food processor and pulsing until smooth.

(Optional)If you want the milkshake to be green in color, Can add 2 or 3 green drops.